US3968949A - Projector tilt mechanism - Google Patents
Projector tilt mechanism Download PDFInfo
- Publication number
- US3968949A US3968949A US05/489,759 US48975974A US3968949A US 3968949 A US3968949 A US 3968949A US 48975974 A US48975974 A US 48975974A US 3968949 A US3968949 A US 3968949A
- Authority
- US
- United States
- Prior art keywords
- shaft
- threaded
- base
- platform
- location
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000007246 mechanism Effects 0.000 title claims abstract description 25
- 230000008878 coupling Effects 0.000 claims 1
- 238000010168 coupling process Methods 0.000 claims 1
- 238000005859 coupling reaction Methods 0.000 claims 1
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 abstract description 8
- 230000008859 change Effects 0.000 abstract description 2
- 230000008901 benefit Effects 0.000 description 6
- 210000001364 upper extremity Anatomy 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000003134 recirculating effect Effects 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16M—FRAMES, CASINGS OR BEDS OF ENGINES, MACHINES OR APPARATUS, NOT SPECIFIC TO ENGINES, MACHINES OR APPARATUS PROVIDED FOR ELSEWHERE; STANDS; SUPPORTS
- F16M11/00—Stands or trestles as supports for apparatus or articles placed thereon ; Stands for scientific apparatus such as gravitational force meters
- F16M11/02—Heads
- F16M11/04—Means for attachment of apparatus; Means allowing adjustment of the apparatus relatively to the stand
- F16M11/06—Means for attachment of apparatus; Means allowing adjustment of the apparatus relatively to the stand allowing pivoting
- F16M11/10—Means for attachment of apparatus; Means allowing adjustment of the apparatus relatively to the stand allowing pivoting around a horizontal axis
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16M—FRAMES, CASINGS OR BEDS OF ENGINES, MACHINES OR APPARATUS, NOT SPECIFIC TO ENGINES, MACHINES OR APPARATUS PROVIDED FOR ELSEWHERE; STANDS; SUPPORTS
- F16M11/00—Stands or trestles as supports for apparatus or articles placed thereon ; Stands for scientific apparatus such as gravitational force meters
- F16M11/02—Heads
- F16M11/18—Heads with mechanism for moving the apparatus relatively to the stand
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B21/00—Projectors or projection-type viewers; Accessories therefor
- G03B21/14—Details
- G03B21/145—Housing details, e.g. position adjustments thereof
Definitions
- This invention relates to load positioning apparatus, and more particularly to a mechanism for supporting a video projector with precisely adjustable pitch or front-to-rear tilt.
- Sophisticated, compact video projectors such as model PJ 5000 available from General Electric Company, Syracuse, N.Y., include a light valve, operating circuitry, and associated apparatus within a common enclosure.
- the weight of the enclosure is generally greater than that of conventional motion picture projectors; for example, the General Electric PJ 5000 projector weighs approximately 125 pounds.
- the unit When the unit is placed into operation at any selected location, it is necessary that the displayed image be properly positioned in the desired area on the display screen. Because the relative height of projector and screen vary from location to location when the apparatus is employed at different locations, it is necessary to provide the projector with a tilt mechanism that can adjust the projector pitch so as to raise or lower the displayed image quickly, precisely, and with minimal effort.
- one object of the invention is to provide a stable projector tilt mechanism that is smoothly and precisely positionable.
- Another object is to provide a rapidly adjustable load tilting mechanism which exhibits a large mechanical advantage.
- Another object is to provide a projector tilt mechanism operable on either a flat surface or a pedestal.
- a mechanism having a platform for tilting a load carried on the platform comprises a threaded shaft and support means engaging the shaft.
- the support means are coupled to the platform so as to maintain the platform generally at a predetermined position with respect to the shaft.
- Threaded means are pivotally mounted at a first location on a base so as to be free to rotate through a vertical plane.
- the threaded means engage the threaded shaft and are rotatable relative to each other.
- the platform is pivotally mounted at a second location upon the base, spaced apart from the first location so as to be free to rotate through a vertical plane.
- FIG. 1 is a partially broken-away perspective view of apparatus embodying the invention
- FIG. 2 is a partially broken-away top view of a portion of the apparatus embodying the invention
- FIG. 3 is a side view of the apparatus embodying the invention, when used in conjunction with a projector, supported on a flat surface;
- FIGS. 4 and 5 are side views of the apparatus embodying the invention, when used to tilt a projector upward or downward, respectively, on a flat surface;
- FIG. 6 is a side view of the apparatus embodying the invention, when used in conjunction with a projector, supported on a pedestal.
- FIG. 1 illustrates apparatus embodying the invention, which includes a platform or frame 10 on which a load, such as a video projector, is to be carried.
- a shaft 11 threaded over most of its length, is coupled to platform 10 through a tee-shaped bushing 12, by pins 13 passing through apertures in either skirt 14 of platform 10 and into solid rod portions 15 on either side of the tee-shaped bushing.
- Platform 10 is thus maintained generally at a predetermined position with respect to shaft 11, though pins 13 are free to pivot within the apertures in platform skirt 14.
- the portion of shaft 11 extending outward from platform 10 beyond bushing 12 is terminated in rotatable means which may be motor driven or manually driven.
- a knob 16 is provided where manual drive is preferred.
- An internally threaded block 20 is pivotally mounted at the apex region 24 of a generally triangularly shaped base 21.
- a pair of nuts 22 are attached by external threads (visible in FIG. 2), to block 20, and allow shaft 11 to rotate within internal threads (visible in FIG. 2).
- Nuts 22, when properly positioned, are affixed in place by set screws 22 passing through block 20.
- a strengthening rib 26 on skirt region 14 of platform 10 is pivotally attached to base 21 near the lowermost portion 25 of the base. Conveniently, block 20 and platform 10 pivot about axes 27 and 28, respectively.
- rotation of shaft 11 serves to rotate frame 10 about axis 28 through a vertical plane orthogonal to axis 28.
- Rotation of knob 16 in one direction e.g., clockwise, tends to shorten the distance between block 20 and tee-shaped bushing 12, causing platform 10 to pivot about axis 28 such that the end of platform 10 closest to knob 16 moves away from the portion of base 21 beneath that region of platform 10.
- rotation of knob 16 in the opposite direction tends to lengthen the distance between block 20 and tee-shaped bushing 12, causing platform 10 to pivot about axis 28 such that the end of platform 10 closest to knob 16 moves toward the portion of base 21 beneath that region of platform 10.
- shaft 11 moves approximately in unison with platform 10 at tee-shaped bushing 12, pivoting about axis 27.
- Bushing 12 pivots slightly about pins 13 as the tilt mechanism pitch changes, since platform 10 and shaft 11 pivot on different centers. Nevertheless, shaft 11 and platform 10 move through the same or parallel vertical planes when the platform is rotated about axis 28. Because the interaction of the threads on shaft 11 with the internal threads of nuts 22 is essentially that of a worm gear, a large mechanical advantage in rotating platform 10 with respect to base 21 is obtained. Moreover, by appropriate worm gear ratios, an optimum balance may be selected between mechanical advantage and degree of pitch change for any given amount of rotation of shaft 11, so that adequate speed of positioning need not be sacrificed for a large mechanical advantage.
- the mechanism by which shaft 11 moves longitudinally through block 20 may comprise a recirculating ball nut and shaft. This provides an extremely low friction coefficient, making the rotational system highly efficient. In such case, however, it may be necessary to clamp the shaft to keep it in position since the weight of the load, when raised, may cause the shaft to rotate and lower itself. If the motor is electrically driven, it may be convenient to employ a solenoid-operated clamp to retain the tilt mechanism in its desired position.
- FIG. 2 illustrates in detail the portion of the apparatus of FIG. 1 responsible for preventing lost motion in the rotational system.
- Lost motion is prevented in block 20 by use of nuts 22 on either side of the block.
- One of nuts 22 is first locked in place using its associated set screw 23, shown in FIG. 1, and then the other of nuts 22 is screwed tightly along shaft 11 toward the locked nut 22 and locked in place with the other of set screws 23.
- Inwardly directed pressures on the threads of shaft 11 are thus applied by nuts 22, which remain stationary with respect to block 20 and prevent axial displacement of shaft 11 without accompanying shaft rotation.
- FIG. 2 also shows a pair of pins 31 centered along axis 27 and extending through apertures on either side of base 21 into block 20 to permit rotation of block 20 about axis 27.
- FIG. 2 also shows pins 13 passed through apertures in skirt 14 of platform 10 and into solid rod portions 15 on either side of tee-shaped bushing 12.
- FIGS. 3-5 illustrate operation of the invention in conjunction with a video projector 50 as the load mounted thereon, and are described accordingly, although the load may be any apparatus for which a precise tilt is desired, limited only by the user's ingenuity.
- projector 50 having a lens 51 from which optical images are projected is illustrated as supported on a pair of front legs 52 (only one of which is visible) and a pair of rear legs 53 (only one of which is visible) standing on a flat surface 54, such as a tabletop.
- Each leg is terminated in a pad 55 free to swivel about the bottom of the respective leg to which it is attached.
- the bottom of projector 50 is fastened to platform 10 of the tilt mechanism such that base 21 is raised entirely above the surface of table 54, knob 16 having been adjusted to maintain base 21 approximately parallel to the surface of table 54. If knob 16 is thereafter rotated, as in a clockwise direction, threaded shaft 11 draws block 20, shown in FIGS. 1 and 2, in a direction toward knob 16, in turn drawing the apex region of base 21 toward knob 16.
- platform 10 and base 21 rotate with respect to each other about pivot axis 28, positioning the projector as illustrated in FIG. 4 whereby the front portion of base 21 bears against surface 54 and raises the front portion of platform 10. Consequently the front portion of projector 50 is raised, and pads 55 attached to front legs 52 are lifted entirely off of surface 54.
- FIG. 6 projector 50 is shown fastened to platform 10 of the tilt mechanism, with base 21 being rigidly fastened at its front and rear portions to a pedestal 60, as by screws 61 passing through upright portions 62 of the pedestal and penetrating into base 21.
- legs 52 and 53 shown in FIGS. 3-5 are unnecessary since the projector is continuously supported by the tilt mechanism only.
- FIGS. 3-5 if knob 16 is rotated, as in a clockwise direction, threaded shaft 11 draws block 20, shown in FIGS. 1 and 2, in a direction toward knob 16, in turn tending to pull the apex region of base 21 toward knob 16. Since the base is fastened to pedestal 60, however, it cannot move.
- lost motion in block 20 and end play of shaft 11 at bushing 12 can be especially detrimental to achieving precise tilt of the load on platform 10 when the center of gravity of the gross load approaches dead center and then goes over center in either forward or rear tilt.
- dead center lies on a vertical plane containing axis 28.
- Jacking, or erratic motion is most noticeable when the projector is pedestal-mounted since, even when the center of gravity of the gross load is at dead center, the load is entirely supported by the tilt mechanism unlike the table-mounted configuration shown in FIGS. 3-5.
- the foregoing describes a stable, load-carrying tilt mechanism that is smoothly and precisely positionable.
- the tilt mechanism which may support a projector, is rapidly adjustable and exhibits a large mechanical advantage.
- the tilt mechanism may be operated on either a flat surface or a pedestal.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Projection Apparatus (AREA)
Abstract
A projector tilt mechanism includes a base about which a load-carrying platform is rotated in a vertical plane. A threaded shaft is rotatably coupled to the platform by radial thrust bearings and to the base by threaded fittings. Lost motion in the rotational system is avoided by properly positioning and locking in place two threaded nuts along the shaft at either side of the threaded connection to the base, and by using threaded locking collars tightened against the outermost thrust bearing faces. Rotation of the shaft produces relative rotation of the platform and base, causing the base to raise the front or rear of the projector above a flat surface or, if the base is affixed to a pedestal, causing a direct change in platform pitch.
Description
This invention relates to load positioning apparatus, and more particularly to a mechanism for supporting a video projector with precisely adjustable pitch or front-to-rear tilt.
Sophisticated, compact video projectors, such as model PJ 5000 available from General Electric Company, Syracuse, N.Y., include a light valve, operating circuitry, and associated apparatus within a common enclosure. The weight of the enclosure is generally greater than that of conventional motion picture projectors; for example, the General Electric PJ 5000 projector weighs approximately 125 pounds. When the unit is placed into operation at any selected location, it is necessary that the displayed image be properly positioned in the desired area on the display screen. Because the relative height of projector and screen vary from location to location when the apparatus is employed at different locations, it is necessary to provide the projector with a tilt mechanism that can adjust the projector pitch so as to raise or lower the displayed image quickly, precisely, and with minimal effort. Because of the heavier weight of a video projector, conventional motion picture projector tilt mechanisms are too flimsy to provide this type of service. Moreover, because there is no tape or film that can be rewound and restarted if video projectors displaying live or broadcast signals should direct images for any length of time outside of the desired zone on the screen, it is essential that the tilt mechanism be stable, so that the picture, once produced in the desired area of the screen, will remain in that area until the pitch of the projector is intentionally readjusted or the entire projector repositioned at some other location. The present invention is directed to apparatus of this type.
Accordingly, one object of the invention is to provide a stable projector tilt mechanism that is smoothly and precisely positionable.
Another object is to provide a rapidly adjustable load tilting mechanism which exhibits a large mechanical advantage.
Another object is to provide a projector tilt mechanism operable on either a flat surface or a pedestal.
Briefly, in accordance with a preferred embodiment of the invention, a mechanism having a platform for tilting a load carried on the platform comprises a threaded shaft and support means engaging the shaft. The support means are coupled to the platform so as to maintain the platform generally at a predetermined position with respect to the shaft. Threaded means are pivotally mounted at a first location on a base so as to be free to rotate through a vertical plane. The threaded means engage the threaded shaft and are rotatable relative to each other. The platform is pivotally mounted at a second location upon the base, spaced apart from the first location so as to be free to rotate through a vertical plane.
The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself, however, both as to organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a partially broken-away perspective view of apparatus embodying the invention;
FIG. 2 is a partially broken-away top view of a portion of the apparatus embodying the invention;
FIG. 3 is a side view of the apparatus embodying the invention, when used in conjunction with a projector, supported on a flat surface;
FIGS. 4 and 5 are side views of the apparatus embodying the invention, when used to tilt a projector upward or downward, respectively, on a flat surface; and
FIG. 6 is a side view of the apparatus embodying the invention, when used in conjunction with a projector, supported on a pedestal.
FIG. 1 illustrates apparatus embodying the invention, which includes a platform or frame 10 on which a load, such as a video projector, is to be carried. A shaft 11, threaded over most of its length, is coupled to platform 10 through a tee-shaped bushing 12, by pins 13 passing through apertures in either skirt 14 of platform 10 and into solid rod portions 15 on either side of the tee-shaped bushing. Platform 10 is thus maintained generally at a predetermined position with respect to shaft 11, though pins 13 are free to pivot within the apertures in platform skirt 14. The portion of shaft 11 extending outward from platform 10 beyond bushing 12 is terminated in rotatable means which may be motor driven or manually driven. A knob 16 is provided where manual drive is preferred.
An internally threaded block 20 is pivotally mounted at the apex region 24 of a generally triangularly shaped base 21. A pair of nuts 22 are attached by external threads (visible in FIG. 2), to block 20, and allow shaft 11 to rotate within internal threads (visible in FIG. 2). Nuts 22, when properly positioned, are affixed in place by set screws 22 passing through block 20. A strengthening rib 26 on skirt region 14 of platform 10 is pivotally attached to base 21 near the lowermost portion 25 of the base. Conveniently, block 20 and platform 10 pivot about axes 27 and 28, respectively.
In operation, rotation of shaft 11 serves to rotate frame 10 about axis 28 through a vertical plane orthogonal to axis 28. Rotation of knob 16 in one direction, e.g., clockwise, tends to shorten the distance between block 20 and tee-shaped bushing 12, causing platform 10 to pivot about axis 28 such that the end of platform 10 closest to knob 16 moves away from the portion of base 21 beneath that region of platform 10. Similarly, rotation of knob 16 in the opposite direction tends to lengthen the distance between block 20 and tee-shaped bushing 12, causing platform 10 to pivot about axis 28 such that the end of platform 10 closest to knob 16 moves toward the portion of base 21 beneath that region of platform 10. In either case, shaft 11 moves approximately in unison with platform 10 at tee-shaped bushing 12, pivoting about axis 27. Bushing 12, however, pivots slightly about pins 13 as the tilt mechanism pitch changes, since platform 10 and shaft 11 pivot on different centers. Nevertheless, shaft 11 and platform 10 move through the same or parallel vertical planes when the platform is rotated about axis 28. Because the interaction of the threads on shaft 11 with the internal threads of nuts 22 is essentially that of a worm gear, a large mechanical advantage in rotating platform 10 with respect to base 21 is obtained. Moreover, by appropriate worm gear ratios, an optimum balance may be selected between mechanical advantage and degree of pitch change for any given amount of rotation of shaft 11, so that adequate speed of positioning need not be sacrificed for a large mechanical advantage.
In the event it is desired to drive shaft 11 by means of a motor, the mechanism by which shaft 11 moves longitudinally through block 20 may comprise a recirculating ball nut and shaft. This provides an extremely low friction coefficient, making the rotational system highly efficient. In such case, however, it may be necessary to clamp the shaft to keep it in position since the weight of the load, when raised, may cause the shaft to rotate and lower itself. If the motor is electrically driven, it may be convenient to employ a solenoid-operated clamp to retain the tilt mechanism in its desired position.
FIG. 2 illustrates in detail the portion of the apparatus of FIG. 1 responsible for preventing lost motion in the rotational system. Lost motion is prevented in block 20 by use of nuts 22 on either side of the block. One of nuts 22 is first locked in place using its associated set screw 23, shown in FIG. 1, and then the other of nuts 22 is screwed tightly along shaft 11 toward the locked nut 22 and locked in place with the other of set screws 23. Inwardly directed pressures on the threads of shaft 11 are thus applied by nuts 22, which remain stationary with respect to block 20 and prevent axial displacement of shaft 11 without accompanying shaft rotation. FIG. 2 also shows a pair of pins 31 centered along axis 27 and extending through apertures on either side of base 21 into block 20 to permit rotation of block 20 about axis 27.
At the free end of platform 10, an unthreaded portion 40 of shaft 11 passes through tee-shaped bushing 12, terminating at knob 16. A hexagonal nut 32 is fastened on a short threaded region 38 of shaft 11 against a thrust collar 33 which, in turn, bears against the outer face of a radial thrust bearing 34. A second hexagonal nut 35 is locked against nut 32 on threaded region 38 of shaft 11 to prevent nut 32 from becoming loosened. The inner face of thrust bearing 34 abuts tee-shaped bushing 12. At the opposite end of bushing 12, a thrust collar 36 is forced against a radial thrust bearing 37 by the end of the lengthy threaded portion 41 of shaft 11, and the inner face of thrust bearing 37 thus bears against bushing 12. Consequently, shaft 11 is free to rotate in bushing 12, but is prevented from axial displacement therein. FIG. 2 also shows pins 13 passed through apertures in skirt 14 of platform 10 and into solid rod portions 15 on either side of tee-shaped bushing 12.
FIGS. 3-5 illustrate operation of the invention in conjunction with a video projector 50 as the load mounted thereon, and are described accordingly, although the load may be any apparatus for which a precise tilt is desired, limited only by the user's ingenuity. In FIG. 3, projector 50 having a lens 51 from which optical images are projected, is illustrated as supported on a pair of front legs 52 (only one of which is visible) and a pair of rear legs 53 (only one of which is visible) standing on a flat surface 54, such as a tabletop. Each leg is terminated in a pad 55 free to swivel about the bottom of the respective leg to which it is attached.
As shown in FIG. 3, the bottom of projector 50 is fastened to platform 10 of the tilt mechanism such that base 21 is raised entirely above the surface of table 54, knob 16 having been adjusted to maintain base 21 approximately parallel to the surface of table 54. If knob 16 is thereafter rotated, as in a clockwise direction, threaded shaft 11 draws block 20, shown in FIGS. 1 and 2, in a direction toward knob 16, in turn drawing the apex region of base 21 toward knob 16. Thus platform 10 and base 21 rotate with respect to each other about pivot axis 28, positioning the projector as illustrated in FIG. 4 whereby the front portion of base 21 bears against surface 54 and raises the front portion of platform 10. Consequently the front portion of projector 50 is raised, and pads 55 attached to front legs 52 are lifted entirely off of surface 54. This leaves the projector supported by its rear legs and the tilt mechanism, and the displayed images are elevated above those that would be produced when the projector is situated as illustrated in FIG. 3. Similarly, if knob 16 should be rotated in the opposite direction, threaded shaft 11 pushes block 20, shown in FIGS. 1 and 2, in a direction away from knob 16, in turn pushing the apex region of the base away from knob 16. Platform 10 and base 21 again rotate with respect to each other about pivot axis 28, positioning the projector as illustrated in FIG. 5 whereby the rear portion of base 21 bears against surface 54 and raises the rear portion of platform 10. Consequently the rear portion of projector 50 is raised, and pads 55 attached to rear legs 53 are lifted entirely off of surface 54. This leaves the projector supported by its front legs and the tilt mechanism, and the displayed images are lowered below those that would be produced when the projector is situated as illustrated in FIG. 3.
In FIG. 6, projector 50 is shown fastened to platform 10 of the tilt mechanism, with base 21 being rigidly fastened at its front and rear portions to a pedestal 60, as by screws 61 passing through upright portions 62 of the pedestal and penetrating into base 21. When the projector is operated in this fashion, legs 52 and 53 shown in FIGS. 3-5 are unnecessary since the projector is continuously supported by the tilt mechanism only. As in the case of FIGS. 3-5, if knob 16 is rotated, as in a clockwise direction, threaded shaft 11 draws block 20, shown in FIGS. 1 and 2, in a direction toward knob 16, in turn tending to pull the apex region of base 21 toward knob 16. Since the base is fastened to pedestal 60, however, it cannot move. Therefore, the end of platform 10 at which knob 16 is located tends to rise, due to relative rotation of platform 10 about pivot axis 28, and the image produced by projector 50 is elevated. Similarly, if knob 16 is rotated in the opposite direction, threaded shaft 11 forces block 20, shown in FIGS. 1 and 2, in a direction away from knob 16, in turn tending to push the apex region of base 21 away from knob 16. However, since the base is fastened to pedestal 60, the end of platform 10 at which knob 16 is located is lowered, due to relative rotation of platform 10 about pivot axis 28. Consequently, images produced by projector 50 are thereby lowered.
Whether the projector is table-mounted, as shown in FIGS. 3-5, or pedestal-mounted, as shown in FIG. 6, lost motion in block 20 and end play of shaft 11 at bushing 12 can be especially detrimental to achieving precise tilt of the load on platform 10 when the center of gravity of the gross load approaches dead center and then goes over center in either forward or rear tilt. In this instance, dead center lies on a vertical plane containing axis 28. Jacking, or erratic motion, is most noticeable when the projector is pedestal-mounted since, even when the center of gravity of the gross load is at dead center, the load is entirely supported by the tilt mechanism unlike the table-mounted configuration shown in FIGS. 3-5. By substantially eliminating lost motion in the rotational system, the aforementioned erratic motion of the load may be avoided.
The foregoing describes a stable, load-carrying tilt mechanism that is smoothly and precisely positionable. The tilt mechanism, which may support a projector, is rapidly adjustable and exhibits a large mechanical advantage. The tilt mechanism may be operated on either a flat surface or a pedestal.
While only certain preferred features of the invention have been shown by way of illustration, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.
Claims (18)
1. A mechanism having a platform for tilting a load carried on said platform, comprising:
a threaded shaft;
support means engaging said shaft and coupled to said platform so as to maintain said platform generally at a predetermined position with respect to said shaft;
a base, having first and second ends, said base being pivotable about said first end thereof for affecting movement of said platform in a first direction, said base being pivotable about said second end thereof for affecting movement of said platform in a second direction, said base pivoting responsive to the rotation of said shaft; and
threaded means pivotably mounted about an axis at a first location upon said base so as to be free to rotate through a first plane substantially orthogonal to said axis, said threaded means engaging said threaded shaft, said threaded means and said threaded shaft being rotatable relative to each other,
said platform being pivotally mounted at a second location upon said base, spaced apart from said first location so as to be free to rotate through a second plane substantially parallel to said first plane.
2. The mechanism of claim 1 wherein said shaft is relatively rotatable with respect to said support means.
3. The apparatus of claim 1 wherein said platform is situated above said threaded shaft, and said second location on said base is located below said first location on said base.
4. The apparatus of claim 2 wherein said platform is situated above said threaded shaft, and said second location on said base is located below said first location on said base.
5. The apparatus of claim 2 including means coupled to one end of said threaded shaft for imparting rotational motion to said shaft.
6. The apparatus of claim 4 including means coupled to one end of said threaded shaft for imparting rotational motion to said shaft.
7. The apparatus of claim 1 wherein said threaded means comprises two threaded fittings, each fitting being separately positionable along said shaft to minimize lost motion between said threaded means and said shaft.
8. The apparatus of claim 2 wherein said threaded means comprises two threaded fittings, each fitting being separately positionable along said shaft to minimize lost motion between said threaded means and said shaft.
9. The apparatus of claim 6 wherein said threaded means comprises two threaded fittings, each fitting being separately positionable along said shaft to minimize lost motion between said threaded means and said shaft.
10. The apparatus of claim 9 including means affixed to said shaft on either side of said support means, and thrust bearings situated between said support means and each of said means affixed to said shaft, said thrust bearings being urged against said support means on either side thereof by said means affixed to said shaft on either side of said support means, respectively.
11. A projector tilt mechanism having a frame for supporting a projector thereon with selectable pitch, comprising:
a threaded shaft rotatable about its longitudinal axis;
support means coupling said shaft to said frame so as to maintain said frame generally at a predetermined position with respect to said shaft, said shaft being free to rotate with respect to said support means;
a base, having first and second ends, said base being pivotable about said first end thereof for affecting movement of said frame in a first direction, said base being pivotable about said second end thereof for affecting movement of said frame in a second direction, said base pivoting responsive to the rotation of said shaft; and
threaded means pivotally mounted about an axis at a first location upon said base so as to be free to rotate through a plane substantially orthogonal to said axis, said threaded means engaging said threaded shaft,
said frame being pivotally mounted at a second location upon said base, spaced vertically apart from said first location so as to be free to rotate through a second plane.
12. The apparatus of claim 11 wherein said frame is situated above said threaded shaft and said second location on said base is located below said first location on said base.
13. The apparatus of claim 12 including means coupled to one end of said threaded shaft for imparting rotational motion to said shaft.
14. The apparatus of claim 11 wherein said threaded means comprises two threaded fittings, each fitting being separately positionable along said shaft to minimize lost motion between said threaded means and said shaft.
15. The apparatus of claim 13 wherein said threaded means comprises two threaded fittings, each fitting being separately positionable along said shaft to minimize lost motion between said threaded means and said shaft.
16. The apparatus of claim 15 including means affixed to said shaft on either side of said support means, and thrust bearings on said shaft situated between said support means and each of said means affixed to said shaft, said thrust bearings being urged against said support means on either side thereof by said means affixed to said shaft on either side of said support means, respectively.
17. The apparatus of claim 10, further including means for holding said base in a fixed position, whereby said base independently supports and tilts said platform about said second location.
18. The apparatus of claim 16, further including means for holding said base in a fixed position, whereby said base independently supports and tilts said frame about said second location.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US05/489,759 US3968949A (en) | 1974-07-18 | 1974-07-18 | Projector tilt mechanism |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US05/489,759 US3968949A (en) | 1974-07-18 | 1974-07-18 | Projector tilt mechanism |
Publications (1)
Publication Number | Publication Date |
---|---|
US3968949A true US3968949A (en) | 1976-07-13 |
Family
ID=23945148
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US05/489,759 Expired - Lifetime US3968949A (en) | 1974-07-18 | 1974-07-18 | Projector tilt mechanism |
Country Status (1)
Country | Link |
---|---|
US (1) | US3968949A (en) |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4040585A (en) * | 1976-05-18 | 1977-08-09 | Socas Eduardo L | Adjustable projector table |
US4180002A (en) * | 1978-07-12 | 1979-12-25 | American Hospital Supply Corporation | Tiltable table |
EP0117639A1 (en) * | 1983-01-28 | 1984-09-05 | Texas Instruments Incorporated | Data display keyboard with angular positioning |
US4518142A (en) * | 1981-07-20 | 1985-05-21 | Whirlpool Corporation | Support and leveling system for refuse compactor |
US5749550A (en) * | 1996-05-28 | 1998-05-12 | General Electric Company | Appliance leveling system allowing adjustment of rear supports without access to rear of cabinet |
US5971408A (en) * | 1997-06-04 | 1999-10-26 | Maytag Corporation | Vertically adjustable wheel assembly |
US6390627B1 (en) * | 1998-07-07 | 2002-05-21 | Seiko Epson Corporation | Projection display device |
US6604722B1 (en) * | 2002-06-10 | 2003-08-12 | Seng-Ling Tan | Display support |
EP1431808A1 (en) * | 2002-12-13 | 2004-06-23 | Sony International (Europe) GmbH | Projector arrangement |
US6871379B2 (en) | 2002-10-01 | 2005-03-29 | Wolf Appliance Company, Llc | Method and apparatus for appliance installation and leveling |
US20080225243A1 (en) * | 2007-03-15 | 2008-09-18 | Coretronic Corporation | Projection apparatus |
CN101144867B (en) * | 2006-09-15 | 2011-11-09 | 富士迈半导体精密工业(上海)有限公司 | Planar regulation device |
US20130009526A1 (en) * | 2011-07-07 | 2013-01-10 | Hsiang-Ming Lu | Footstand mechanism for adjusting a tilt angle of an electronic device and electronic device therewith |
US20130206943A1 (en) * | 2012-02-15 | 2013-08-15 | Peerless Insdustries, Inc. | Mounting system for use with audio/visual devices or the like |
US9546756B1 (en) * | 2015-11-10 | 2017-01-17 | Modernsolid Industrial Co., Ltd. | Display supporting apparatus |
CN108167606A (en) * | 2018-02-13 | 2018-06-15 | 福清展旭电子有限公司 | The projector bolster and its application method of high loadability |
CN108413201A (en) * | 2018-05-04 | 2018-08-17 | 福清展旭电子有限公司 | The hoisting mechanism and its working method of image documentation equipment installation frame |
US20180347822A1 (en) * | 2017-05-30 | 2018-12-06 | Samsung Electronics Co., Ltd. | Home appliance |
CN112066199A (en) * | 2020-09-01 | 2020-12-11 | 付金明 | Projector base for holographic projection technology |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2662708A (en) * | 1950-12-29 | 1953-12-15 | Lovejoy Flexible Coupling Co | Tiltable support |
US2696961A (en) * | 1950-09-01 | 1954-12-14 | Eastman Kodak Co | Elevating mechanism |
US2842982A (en) * | 1954-08-28 | 1958-07-15 | Holdener Simeon | Movement transmission |
US3071887A (en) * | 1960-02-11 | 1963-01-08 | Revco Inc | Leveling apparatus |
US3668940A (en) * | 1970-07-09 | 1972-06-13 | Curtiss Wright Corp | Rotation transmission mechanism |
US3750989A (en) * | 1971-07-19 | 1973-08-07 | Maytag Co | Adjustable appliance support |
-
1974
- 1974-07-18 US US05/489,759 patent/US3968949A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2696961A (en) * | 1950-09-01 | 1954-12-14 | Eastman Kodak Co | Elevating mechanism |
US2662708A (en) * | 1950-12-29 | 1953-12-15 | Lovejoy Flexible Coupling Co | Tiltable support |
US2842982A (en) * | 1954-08-28 | 1958-07-15 | Holdener Simeon | Movement transmission |
US3071887A (en) * | 1960-02-11 | 1963-01-08 | Revco Inc | Leveling apparatus |
US3668940A (en) * | 1970-07-09 | 1972-06-13 | Curtiss Wright Corp | Rotation transmission mechanism |
US3750989A (en) * | 1971-07-19 | 1973-08-07 | Maytag Co | Adjustable appliance support |
Cited By (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4040585A (en) * | 1976-05-18 | 1977-08-09 | Socas Eduardo L | Adjustable projector table |
US4180002A (en) * | 1978-07-12 | 1979-12-25 | American Hospital Supply Corporation | Tiltable table |
US4518142A (en) * | 1981-07-20 | 1985-05-21 | Whirlpool Corporation | Support and leveling system for refuse compactor |
EP0117639A1 (en) * | 1983-01-28 | 1984-09-05 | Texas Instruments Incorporated | Data display keyboard with angular positioning |
US5749550A (en) * | 1996-05-28 | 1998-05-12 | General Electric Company | Appliance leveling system allowing adjustment of rear supports without access to rear of cabinet |
US5971408A (en) * | 1997-06-04 | 1999-10-26 | Maytag Corporation | Vertically adjustable wheel assembly |
US6390627B1 (en) * | 1998-07-07 | 2002-05-21 | Seiko Epson Corporation | Projection display device |
US6604722B1 (en) * | 2002-06-10 | 2003-08-12 | Seng-Ling Tan | Display support |
US6871379B2 (en) | 2002-10-01 | 2005-03-29 | Wolf Appliance Company, Llc | Method and apparatus for appliance installation and leveling |
EP1431808A1 (en) * | 2002-12-13 | 2004-06-23 | Sony International (Europe) GmbH | Projector arrangement |
CN101144867B (en) * | 2006-09-15 | 2011-11-09 | 富士迈半导体精密工业(上海)有限公司 | Planar regulation device |
US20080225243A1 (en) * | 2007-03-15 | 2008-09-18 | Coretronic Corporation | Projection apparatus |
US7901091B2 (en) * | 2007-03-15 | 2011-03-08 | Coretronic Corporation | Projection apparatus |
US8807497B2 (en) * | 2011-07-07 | 2014-08-19 | Wistron Corporation | Footstand mechanism for adjusting a tilt angle of an electronic device and electronic device therewith |
US20130009526A1 (en) * | 2011-07-07 | 2013-01-10 | Hsiang-Ming Lu | Footstand mechanism for adjusting a tilt angle of an electronic device and electronic device therewith |
US9976697B2 (en) | 2012-02-15 | 2018-05-22 | Peerless Industries, Inc. | Mounting system for use with audio/visual devices or the like |
US8746642B2 (en) * | 2012-02-15 | 2014-06-10 | Peerless Industries, Inc. | Mounting system for use with audio/visual devices or the like |
US9388938B2 (en) | 2012-02-15 | 2016-07-12 | Peerless Industries, Inc. | Mounting system for use with audio/visual devices or the like |
US20130206943A1 (en) * | 2012-02-15 | 2013-08-15 | Peerless Insdustries, Inc. | Mounting system for use with audio/visual devices or the like |
US9546756B1 (en) * | 2015-11-10 | 2017-01-17 | Modernsolid Industrial Co., Ltd. | Display supporting apparatus |
US20180347822A1 (en) * | 2017-05-30 | 2018-12-06 | Samsung Electronics Co., Ltd. | Home appliance |
US10663175B2 (en) * | 2017-05-30 | 2020-05-26 | Samsung Electronics Co., Ltd. | Home appliance |
CN108167606A (en) * | 2018-02-13 | 2018-06-15 | 福清展旭电子有限公司 | The projector bolster and its application method of high loadability |
CN108167606B (en) * | 2018-02-13 | 2024-01-19 | 福清展旭电子有限公司 | Projector carrier with high load capacity and method of use thereof |
CN108413201A (en) * | 2018-05-04 | 2018-08-17 | 福清展旭电子有限公司 | The hoisting mechanism and its working method of image documentation equipment installation frame |
CN108413201B (en) * | 2018-05-04 | 2024-06-04 | 福清展旭电子有限公司 | Hoisting mechanism of image equipment installation frame and working method thereof |
CN112066199A (en) * | 2020-09-01 | 2020-12-11 | 付金明 | Projector base for holographic projection technology |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3968949A (en) | Projector tilt mechanism | |
US4575033A (en) | Tilt-swivel base for a CRT display terminal | |
US5088676A (en) | Compact height adjustable base for a display | |
US4567835A (en) | Manual adjustable terminal table | |
US4640485A (en) | Adjustable support for display monitor | |
US4570892A (en) | Tiltable rotating display monitor mount | |
US4515087A (en) | Height adjustable table | |
US4516751A (en) | Wall bracket system | |
US4415136A (en) | Pedestal for consoles | |
US6149253A (en) | Video display positioning system | |
US5997147A (en) | TV viewing system | |
GB2171002A (en) | Adjustable computer work table | |
EP0160237A1 (en) | Tiltable cathode ray tube display device structure | |
US5622348A (en) | Projector mounting and alignment device | |
US4349173A (en) | Tilt device for use with cathode ray tube display units | |
US4539913A (en) | Work table | |
JPH05126134A (en) | Tilting device | |
US4842402A (en) | Projection and viewing apparatus | |
CN113551125A (en) | But high definition laser projector of angular rotation adjustment | |
US2326542A (en) | Photographic enlarger | |
CN219982491U (en) | Contrast picture fixing table | |
CN219692781U (en) | Projector adjusting structure | |
US11906103B1 (en) | Liftable television floor stand | |
JPS60124183A (en) | Supporting device having inclining mechanism | |
JPH04355441A (en) | Projector table having adjustor |